Tainted Fuel

After residual fuel has been sitting in my carb for a few days, it turns yellow. What is causing this? I've been draining the carb after each use and the fuel is treated with Stabil.

Air and sunlight degrade fuel. Moisture is also present in the air and methanol or ethanol fuels absorb moisture from the air. Your carb is vented thus air will degrade the fuel in the carb if it sits up for a while. I plug up my fuel tank vent on my bike if it will be sitting for more than a week.

After a few days your fuel should not be going yellow .!!(Unless your leaving outside without a petrol cap and your cats using the tank as a toilet)!!check the tank for dirt fuel lines etc, ever used any additives,flush it clean ... ..could be bad fuel try getting your fuel elsewhere and see if it does the same ...that cant be right ...Let us know what gives ..

When I first bought the bike a couple months ago, it had some stale gas in it, which I drained out.  I put in some fresh 93 octane and mixed in a couple ounces of Stabil.  I first noticed the tinged fuel upon pulling out my freshly cleaned carburetor in order to adjust the float.  There were traces of yellow-ish brown fuel inside the bowl and on the slow air jet.  Perhaps the fresh fuel and Stabil is cleansing the tank and flushing residue into the carb?

when i used to buy old bikes if the tank looked like it had bad fuel in it from sitting too long i would buy BB pellets and weigh a jar full put them in the tank and swish it about with some cleaner i would keep doin this until i got no more bits when flushing !i am sure there is a better way to do it but that worked for me ..i must just say i have left fuel in bikes for months even years and i have never had discolouration or gumming up of the jets ,i always garage my bikes after riding ,drain the carb ,if i know the bike is going to sit i will empty the tank and over fill all the oil levels just to stop condensation ..i have never come across fule going off in a few days ..?keep us informed of what you find out ..

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